Kururin - the Rolling Stick

Introduction: Kururin - the Rolling Stick

Kururin's are a new skill/fidget toy from Japan, the body is just made of wood and easy to turn on a lathe. I've designed two tools to help you make a Kururin for yourself.

The Kururin Gauge contains all the measurements you need on one handy tool: length, half length, middle diameter and end diameter. No need to have a ruler or keep changing caliper dimensions! The second tool is the Kururin Sanding Jig, which is a cradle to hold the Kururin while you finish the ends using a disc sander. Without it, your Kururin probably won't stand vertical and proud. With it, you'll have perfect ends every time!

I have made a 5 minute how-to video if you prefer to watch a video. It's attached to this step or you can watch it here: How to make a Kururin.

If you can't make the gauge or the jig don't worry, it's still possible to make a Kururin without them, so what are you waiting for? Let's make a Kururin!

Tools

Wood lathe

Roughing gouge

Skew chisel or a scraper

Sandpaper, friction polish and beeswax (none are strictly essential but you'll have a better Kururin if you use them).

Step 1: Turn the Kururin on the Lathe

There are quite a few steps in this "Step" but I think it's best to keep all the lathe work together. The step after this one explains how to finish the Kururin so don't take it off the lathe until you've finished that step!

Mount the wood blank (a dense hardwood rolls best) and using a roughing gouge to make it round.

Make a groove at one end of the blank using the parting tool.

Use the Kururin Gauge to mark the length (90mm) of the Kururin.

The parting tool is used again to make a groove 90mm from the other one.

A skew chisel (the tool I used) or scraper is used to get the middle diameter (27mm). Don't forget the Kururin Gauge has a cut out for this dimension!

Mark the middle with a pencil.

Use the skew chisel or scraper to get the correct end diameter on one side (20mm).

Continue using the skew chisel or scraper to get the profile on that side close to what it should be. Be careful not to remove too much material, you can only take away wood, you can't put it back!

Do the same for the other side.

Check the profile with the Kururin Gauge, if it isn't good, try and fix it.

If you want to have small grooves near the end, use a skew chisel to do this.

Don't take it off the lathe yet! You need to sand, polish and wax it first!

Step 2: Sand, Polish and Wax

The title of this step is almost everything you need to know.

You will need to start with coarse sandpaper before working down to fine sandpaper. Before you being, turn the speed of the lathe down. After every grade, turn the lathe off and sand with the grain to remove the score marks.

Once all the sanding is turn apply a few coats of friction polish. Turn the speed of the lathe back up for this step.

Apply some layers of beeswax until your Kururin has a glorious sheen!

Now you can take the Kururin off the lathe.

Step 3: Finish the Ends

You could use the parting tool to reduce the diameter of the wood next to the ends but I find this to be a risk strategy because the wood can break and the Kururin will fly off the lathe, probably damaging it. Since you've just got it perfect, you don't want that!

Use a bandsaw or just a regular saw to remove most of the material at the ends but don't go too close too the ends. I use the Kururin Sanding Jig for this step but it's not essential.

Make sure the miter fence is perpendicular to the disc sander sandpaper using a set square. If you don't do this then there is no point using the jig I designed for you!

Hold the Kururin firmly in the Kururin Sanding Jig and place it against the mitre gauge. Gently push it into the disk and get that end perfect.

Check you have done a good job by putting the Kururin on a flat surface and rotate it on its axis. If it wobbles then things haven't gone well. If it stand vertical the whole way round, well done! All the hard work is done.

Step 4: Pad Up

Silicone pads at the end greatly improve play because they stop the Kururin from slipping so it's working spending the time to make them.

I use compass cutters to make the circle. Get the radius from one end of the Kururin.

Silicone glue/sealant works well to stick the pads on. Silicone is a bit of a pain to stick with most types of glue but I have found Poundland (if you're in the UK) has cheap silicone glue that works well. Apply a very thin layer! Less is better for this.

Step 5: Kururin Gauge

The Kururin Gauge was designed using Inkscape and OpenSCAD. I cut it out using a laser cutter and acrylic but I have included an STL file for 3D printers. At a pinch you could print it on paper, stick it to card-stock and cut it out. The files are attached to this step but if you want to edit them, visit my website for all the design files.

There is no special weighting or anything, I think the shape is the main factor. I would like to generate a cyclogon because I think that would aid understanding but I haven't spent the time to figure out how to do that yet.

Ah interesting. Maybe it's because the center of gravity moves very fast horizontally when rolling and then very fast vertically. So the duration in the vertical position where it can come to rest is "longer" during the motion and it has a kind of stability because of that.

Please post yours! It would be especially good if you could fill in the gaps I left. In my instructable I assumed the reader was reasonably competent with a lathe because I don't feel qualified enough to cover it thoroughly. I also see you have dyed yours, which I haven't tried yet so I would enjoy following your instructions on that.